Total joint arthroplasty is the surgical replacement of a joint with a prosthesis. A typical knee prosthesis has three main components: a femoral implant, a tibial implant, and a tibio-femoral insert. In general, the femoral component is designed to replace the distal femoral condyles and is typically made from metal. It typically includes rounded surfaces to emulate the condyles, and an elongated stem or pegs for anchoring to the distal femur. In general, the tibial implant is designed to support and align the tibio-femoral insert. The tibial component is also typically made from metal. It typically includes a substantially planar plate portion for supporting the insert and an elongated stem for anchoring to the proximal tibia. In general, the tibio-femoral insert is designed to replace the tibial plateau and the meniscus of the knee. It is typically somewhat disk-shaped and typically includes one or more substantially planar surfaces that bear on the top of the tibial implant and one or more generally concave surfaces that bear against the rounded surfaces of the femoral implant. The insert is generally made of a strong, smooth and low wearing plastic.
Among those benefits and improvements that have been disclosed, other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying figures. The figures constitute a part of this specification and include illustrative embodiments of the present invention and illustrate various objects and features thereof.